Gardening Articles: Care :: Soil, Water, & Fertilizer

Garden Grinders (page 3 of 4)

by Michael MacCaskey

The Rotor

This holds the shredding hammers and chipper blade or blades. When buying a chipper-shredder, remember that rotors on clutch-equipped machines are supported by a center axle mounted on bearings at both ends. On direct-drive machines, the rotor is fitted directly onto the engine's crankshaft, which puts an extra load on the engine's main bearings. Some direct-drive chipper-shredders, add a bearing to support the end of the crankshaft, a feature that lengthens engine life significantly.

Engines

Horsepower is not the only factor determining shredder efficiency. The number of cutting knives, presence and kind of a clutch, and the size of the shredding intake throat are also important. Despite the power of the engine or the size of t hopper, if the intake throat is small you'll need either to feed debris in slowly, or use a tamper to force it down. Also, bigger engines take more muscle to start with a pull cord.

Safety Precautions

For your own safety, read and follow all the manufacturer's precautions. Most are obvious: Don't let kids play in the area while the machine is operating, don't stand and load the machine from the discharge side, always wear work gloves, and eye and ear protection; and avoid loose-fitting clothes, scarves, ties, or anything that might get caught in moving parts.

Most important is the caution, "Wear eye protection." It's always sensible, but in the case of chipper-shredders, there is a real risk. Although no stray projectiles came my way in the many hours I spent working with these machines, it can happen. Most often the debris is launched from the hopper or chipper chute, but it sometimes sneaks out around the collection bag's attachment point. Wherever it originates, it often comes fast and hard.

If the machine becomes jammed, turn it off, disconnect the spark plug, and wait for all moving parts to stop before investigating with your hands.

Another safety issue is the suction that develops, particularly on machines designed to double as vacuums. Make sure nothing except yard waste gets near this down draft. A coworker was shaking debris out of a plastic garbage sack into the shredder hopper, and the bag was sucked right out of his hands. No damage was done, but the experience was unnerving.

One necessity not always mentioned in the product manuals is a pair of loppers at your side while chipping. A few branches with forks and nubs always refuse to slide all the way down the chipper chute. You need loppers to modify these troublemakers. Of course, when not using them, keep them away from the intake openings of the machine.

Michael MacCaskey is the editorial director at the National Gardening Association.